UNIVERSITY  OF  CALIFORNIA  PUBLICATIONS 

COLLEGE  OF  AGRICULTURE 

AGRICULTURAL  EXPERIMENT  STATION 

BERKELEY,  CALIFORNIA 


STOCK   POISONING    PLANTS 
OF  CALIFORNIA 

BY 
HARVEY  MONROE  HALL  and  HARRY  S.  YATES 


BULLETIN  No.  249 

Berkeley,  Cal.,  March,  1915 


UNIVERSITY  OF  CALIFORNIA  PRESS 
BERKELEY 
1915 


Benjamin  Ide  Wheeler,  President  of  the  University. 

EXPERIMENT  STATION  STAFF 
Heads  of  Divisions 
Thomas  Forsyth  Hunt,  Director. 

Eugene  W.  Hilgard,  Agricultural  Chemistry  (Emeritus). 
Edward  J.  Wickson,  Horticulture. 

Herbert  J.  Webber,  Director  Citrus  Experiment  Station;  Plant  Breeding: 
Hubert  E.  Van  Norman,  Vice-Director;  Dairy  Management. 
William  A.  Setchell,  Botany. 
Myer  E.  Jaffa,  Nutrition. 

Robert  H.  Loughridge,  Soil  Chemistry  and  Physics  (Emeritus). 
Charles  W.  Woodworth,  Entomology. 
Ralph  E.  Smith,  Plant  Pathology. 
J.  Eliot  Coit,  Citriculture. 
John  W.  Gilmore,  Agronomy. 
Charles  F.  Shaw,  Soil  Technology. 

John  W.  Gregg,  Landscape  Gardening  and  Floriculture. 
Frederic  T.  Bioletti,  Viticulture  and  Enology. 
Warren  T.  Clarke,  Agricultural  Extension. 
John  S.  Burd,  Agricultural  Chemistry. 
Charles  B.  Lipman,  Soil  Chemistry  and  Bacteriology. 
Clarence  M.  Haring,  Veterinary  Science  and  Bacteriology. 
Ernest  B.  Babcock,  Genetics. 
Gordon  H.  True,  Animal  Husbandry. 
James  T.  Barrett,  Plant  Pathology. 
Fritz  W.  Woll,  Animal  Nutrition. 
A.  V.  Stubenrauch,  Pomology. 
Walter  Mulford,  Forestry. 
W.  P.  Kelley,  Agricultural  Chemistry. 
William  G.  Hummel,  Agricultural  Education. 
Leon  M.  Davis,  Dairy  Industry. 
John  E.  Dougherty,  Poultry  Husbandry. 
Frank  Adams,  Irrigation  Practice. 
David  N.  Morgan,  Assistant  to  the  Director. 
Mrs.  D.  L.  Bunnell,  Librarian. 


STOCK   POISONING  PLANTS  OF  CALIFORNIA 

By  HARVEY  MONROE  HALL  and  HARRY  S.  YATES 


INTRODUCTION 

Although  much  remains  to  be  learned  concerning  the  poisoning  of 
stock  by  plants  in  California  the  subject  is  of  such  importance  that 
it  seems  wise  to  place  before  the  stockmen  and  veterinarians  of  the 
state  a  synopsis  of  our  present  knowledge  concerning  these  matters. 
In  preparing  this  publication  the  aim  has  been  to  adhere  very  closely 
to  established  facts  and  principles  rather  than  to  discuss  mere 
theories  as  to  the  causes  of  poisoning  and  proposed  remedies.  The 
ability  to  recognize  poisonous  plants  and  to  distinguish  them  from 
harmless  ones  is  of  the  greatest  importance  to  practical  stockmen, 
since  by  the  application  of  this  knowledge  they  will  be  able  to  keep 
their  animals  away  from  infested  areas  during  the  seasons  of  greatest 
danger.  The  descriptions  and  illustrations  here  given,  as  well  as  the 
discussions  regarding  distribution  and  habitat,  should  be  of  value  in 
this  connection. 

POPULAR  TREATMENT   OF  POISONED  ANIMALS 

The  prevalent  theory  that  poisoned  animals  should  be  kept  moving 
is,  in  most  cases,  entirely  wrong.  On  the  contrary  they  should  ordin- 
arily be  kept  as  quiet  as  possible,  for  the  high  pulse  and  rapid  breath- 
ing, which  usually  follows  plant  poisoning,  indicate  a  high  state  of 
excitement  and  this  would  be  only  aggravated  by  forced  exercise. 
The  only  exception  is  when  the  poison  exerts  a  depressing  action  on 
the  heart  and  drowsiness  sets  in.  In  this  case  heart  action  should  be 
increased,  preferably  through  the  administration  of  stimulants,  such 
as  whisky,  ammonia,  etc.  Cattle  when  down  should  always  be  urged 
to  assume  the  position  of  normal  repose,  i.e.,  resting  on  the  breast 
bone.    In  case  the  ground  is  sloping  the  head  should  be  up  hill. 

The  practice  of  indiscriminately  bleeding  all  animals  showing 
symptoms  of  plant  poisoning  is  of  very  doubtful  value.  It  is  useful 
only  for  the  purpose  of  relieving  the  blood  pressure  and  should  never 
be  resorted  to  if  the  heart  action  is  weak.  At  best,  bleeding  lowers 
the  vitality  and  affords  only  temporary  relief.  Present-day  veter- 
inarians are  rapidly  learning  to  substitute  better  methods  for  this 
relic  of  mediaeval  medical  practice. 

[219] 


220  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

Melted  lard  and  other  fatty  substances  are  often  administered 
with  beneficial  results,  and  are  especially  valuable  where  other  remedies 
are  not  available.  These  substances  act  as  mild  laxatives,  thus  en- 
abling the  system  to  eliminate  poisonous  matter,  and  at  the  same 
time  serve  to  coat  the  walls  of  the  alimentary  tract  and  so  tend  to 
check  absorption  of  the  poison. 

Soda  is  useful  for  the  purpose  of  neutralizing  acid  poison  but 
should  not  be  administered  if  the  stomach  is  already  alkaline.  Simil- 
arly the  administration  of  vinegar,  which  is  an  acid,  will  be  found 
beneficial  in   case   the  stomach   contents  show   an   alkaline   reaction. 

Bloat  sometimes  occurs  as  a  secondary  effect  in  plant  poisoning. 
It  may  be  reduced  by  standing  the  animal  in  such  a  position  that  the 
front  feet  are  on  a  much  higher  plane  than  the  rear  feet,  and  tying 
a  stick  in  the  mouth  like  a  bit  to  keep  the  jaws  wide  apart.  As  a 
last  resort  the  animal  may  be  relieved  by  means  of  a  trocar  or  sharp 
knife  as  in  other  cases  of  bloat,  provided  the  attendant  is  familiar 
with  the  procedure  in  this  operation. 

PERMANGANATE  QF  POTASH  AS  AN  ANTIDOTE 

More  valuable  by  far  than  any  of  the  above  mentioned  remedies 
is  permanganate  of  potash.  This  chemical  was  especially  recom- 
mended by  Chesnut  and  Wilcox  in  their  pioneer  work  on  the  stock- 
poisoning  plants  of  Montana,  and  though  more  recent  investigations 
indicate  that  it  is  not  so  effective  as  they  then  supposed,  it  is  neverthe- 
less a  very  valuable  remedy,  especially  in  cases  where  other  and  more 
specific  antidotes  are  unknown. 

Permanganate  of  potash,  through  its  strong  oxidizing  action,  at- 
tacks and  breaks  down  most  of  the  plant  poisons.  This  oxidizing  action 
is  accelerated  when  the  substance  to  be  treated  is  acid  in  reaction. 
The  contents  of  the  stomachs  of  animals  are  very  often  only  slightly 
acid,  or  in  some  cases  may  be  even  alkaline.  Because  of  this  fact 
it  has  been  found  advantageous  to  administer  with  the  permanganate 
some  other  chemical  which  will  increase  the  acidity.  Sulfate  of 
aluminum  is  used  for  this  purpose  since  it  is  easily  administered  and 
is  not  so  dangerous  as  the  acids  themselves.  Permanganate  of  potash 
and  sulfate  of  aluminum  are  quite  inexpensive  and  are  carried  by  all 
druggists. 

In  practice  it  has  been  found  that  best  results  are  obtained  when 
equal  amounts  of  the  two  chemicals  are  used.  The  table  below  indicates 
the  dosage  for  adult  animals.  For  younger  stock  the  amount  snould 
be  somewhat  reduced. 


Bulletin  249         STOCK  POISONING  PLANTS  OF   CALIFORNIA  221 

Sheep  and  hogs  Horses  Cattle 

Permanganate  of  potash       5  to  10  grains         15  to  20  grains         30  to  50  grains 
Sulfate  of  aluminum  5  to  10  grains         15  to  20  grains         30  to  50  grains 

The  thoroughly  pulverized  chemicals  are  first  dissolved  in  a  pint 
to  a  quart  of  pure  hot  water  and  after  cooling,  the  solution  is  admin- 
istered as  a  drench.  Great  care  must  be  exercised  to  insure  a  complete 
solution  of  the  permanganate  since  any  undissolved  crystals  may 
lodge  in  the  mucous  membrane  of  the  mouth  and  throat  and  set  up  a 
serious  irritation.  The  powder  should  be  added  to  the  water,  the 
solution  thoroughly  stirred  and  allowed  to  settle  for  several  minutes, 
the  solution  is  then  drawn  off  and  any  dregs  which  may  remain  in  the 
bottom  discarded.  All  organic  matter,  such  as  sugar,  syrup,  etc., 
must  be  kept  out  of  the  liquid  and  the  water  used  should  not  be 
strongly  alkaline. 

For  practical  purposes  large  quantities  of  the  antidote  are  some- 
times made  up  and  kept  on  hand.  The  objection  to  this  practice  is 
that  the  solution  loses  its  power  in  time.  A  better  method  is  to  have 
the  chemicals  put  up  m  powder  form,  each  powder  containing  the 
requisite  quantity  for  one  animal.  These  may  then  be  dissolved  as 
needed. 

In  the  application  of  this  remedy  the  time  element  is  most  im- 
portant. The  permanganate  is  only  effective  on  the  poison  while  it 
is  in  the  stomach;  it  has  no  effect  after  the  poison  has  once  entered 
the  blood;  hence  the  importance  of  administering  the  antidote  at  the 
earliest  possible  moment.  In  case  the  animal  gives  evidence  of  im- 
provement after  the  first  dose  but  again  lapses  into  its  previous  condi- 
tion the  dose  should  be  repeated. 

WATER  HEMLOCK    (Cicuta  species) 
(Umbelliferae,  or  Parsley  Family) 
Names. — Water  hemlock  is  sometimes  called  cowbane,  poison  par- 
snip, and  wild  parsnip.    The  true  parsnips,  as  well  as  the  cow  parsnip, 
are  related  but  quite  different  plants  and  are  not  dangerous  to  stock. 

Description. — Water  hemlock  is  a  tall  branching  perennial  herb,  two  to  five 
feet  high.  The  smooth  hollow  stems  grow  erect  from  a  stout  enlarged  root- 
stock  or  from  a  cluster  of  rootstocks  which  are  characterized  by  having  a  central 
hollow  space  divided  by  cross  partitions  into  chambers,  as  is  shown  in  figure  1. 
This  structure  of  the  underground  parts  is  very  characteristic  and  if  they 
are  examined  there  will  be  little  chance  of  mistaking  any  other  plant  for 
water  hemlock.  The  leaves  are  doubly  pinnately  compound  or  sometimes 
simply  pinnate;  the  edges  of  the  leaflets  are  finely  toothed.  The  small  white 
flowers  are  borne  in  compound  umbels  and  are  followed  by  the  numerous 
seed-like  fruits,  which  resemble  those  of  parsley. 


222  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

The  only  plants  likely  to  be  confused  with  water  hemlock  and  possessing 
similarly  chambered  rootstocks  are  Coelopleurum  maritimum,  a  rare  plant  of 
our  northwest  coast,  and  water  parsnip  (Slum  cicutaefolium).  The  former  is 
probably  itself  poisonous.  The  water  parsnip,  which  never  causes  poisoning, 
differs  from  most  species  of  water  hemlock  in  its  leaves,  which  are  simply 
pinnate.  However,  one  species  of  water  hemlock  also  has  leaves  of  this  type 
and  since  the  other  characters  used  to  distinguish  these  two  groups  of  plants 
are  highly  technical  it  is  advisable  to  submit  doubtful  specimens  to  a  botanist 
for  determination. 

Distribution  and  habitat. — Although  the  several  species  of  water 
hemlock  are  widely  distributed  in  western  North  America  they  are  all 
limited  to  moist  or  even  wet  ground.  The  California  species  grow 
mostly  in  marshes,  often  with  tule,  and  in  low  wet  meadows,  especially 
along  the  streams.  Sometimes  they  form  narrow  borders  along  moun- 
tain streams  and  around  springs. 

Poisonous  characters. — All  parts  of  the  plant  are  poisonous  because 
of  the  presence  of  a  resin  known  as  cicutoxin.  The  resin  is  partic- 
ularly abundant  in  the  rootstocks,  of  which  it  is  said  that  a  piece 
the  size  of  a  walnut  contains  enough  poison  to  kill  a  cow.  These 
underground  parts  are  likely  to  be  trampled  out  of  the  soft  wet  ground 
in  which  they  grow  and  are  then  readily  eaten.  Animals  are  also 
sometimes  poisoned  through  feeding  on  hay  containing  portions  of 
water  hemlock.  Experiments  carried  on  at  the  University  of  Wash- 
ington indicate  that,  in  one  species  at  least,  a  larger  quantity  of  the 
toxic  substance  is  contained  in  the  plant  in  the  fall  and  winter  months. 
Cattle,  horses,  and  sheep  all  eat  the  plant. 

Symptoms. — Symptoms  of  severe  pain  appear  very  soon ;  some- 
times within  fifteen  minutes.  The  first  indication  of  poisoning  is  a 
tendency  to  run  away  from  the  herd.  Within  a  very  short  time  there 
appear  symptoms  of  cerebral  frenzy  along  with  involuntary  muscular 
movements  resembling  those  made  by  animals  suffering  from  colic. 
There  is  frequently  an  increase  in  the  flow  of  saliva.  The  pupils  are 
often  widely  dilated.  Respiration  is  labored  and  somewhat  irregular; 
the  pulse  is  wiry  and  intermittent.  As  the  attack  proceeds  the  mus- 
cular spasms  become  more  and  more  severe  and  cerebral  excitement 
increases  until  the  animal  appears  to  be  unconscious  and  finally  dies. 
The  duration  of  the  attack  is  usually  very  brief;  sometimes  death 
ensues  within  fifteen  minutes  but  more  often  in  two  or  three  hours. 
In  very  mild  cases  the  animal  may  live  for  a  day  or  two.  In  cattle 
and  sheep  there  may  be  bloating  in  mild  cases.  The  poison  has  a 
corrosive  effect  upon  the  walls  of  the  stomach,  which  become  dark  in 
color  and  much  softened.     Frequently  there  may  be  found  pieces  of 


Bulletin  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA 


223 


Fig.  1.  Water  hemlock  (Cicuta  occidentalis) .  One-half  natural  size. 
Water  hemlock  grows  in  moist  or  wet  ground.  The  underground  portion 
contains  most  of  the  poison.  Cattle,  horses,  and  sheep  are  poisoned  by 
water  hemlock.     The  leaves  are  sometimes  much  narrower  than  here  figured. 


224  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

the  characteristic  rootstock  of  water  hemlock  in  which  case  there  is  no 
doubt    as  to  the  plant  responsible. 

Remedies. — The  toxic  substance  contained  in  water  hemlock  is 
so  rapid  in  its  action  that  any  remedy  must  be  administered  very 
promptly.  If  the  symptoms  are  already  apparent  morphine  may  be 
injected  hypodermically  to  allay  the  pain.  The  dose  is  1%  grains  for 
sheep,  3  to  7  grains  for  horses  and  3  to  10  grains  for  cattle.  Melted 
lard  or  any  fatty  substance  might  also  be  effective  if  given  soon  after 
the  first  symptoms  appear.  It  is  doubtful  whether  permanganate  of 
potash  would  be  effective  in  case  of  poisoning  by  water  hemlock.  An 
emetic  followed  by  a  cathartic  would  perhaps  be  more  effective,  the 
object  being  to  eliminate  the  poison  from  the  stomach  as  soon  as 
possible. 

Preventive  measures. — As  in  the  case  of  other  poisonous  plants 
the  first  step  to  be  taken  in  prevention  is  to  become  acquainted  with 
the  plant  so  that  it  may  be  distinguished  from  harmless  species  of  the 
parsley  family.  Since  water  hemlock  is  restricted  to  wet  places  this 
at  once  eliminates  a  great  many  plants  which  might  be  taken  for  it. 
The  most  characteristic  feature  of  the  plant  is  the  structure  of  the 
underground  parts,  seen  especially  well  in  a  longitudinal  section  of 
the  rootstock  (see  figure  on  page  223). 

Since  the  plants  often  occur  only  in  rather  circumscribed  areas 
and  then  usually  not  in  great  number,  eradication  by  digging  will  be 
found  feasible  in  many  cases.  If  dug  out  the  plants  should  not  be 
left  where  stock  can  reach  them.  If  eradication  by  digging  is  not 
feasible  stock  should  be  fenced  away  from  areas  on  which  water  hem- 
lock grows.  It  not  infrequently  happens  that  the  weed  is  much  less 
plentiful  than  one  would  think  from  the  number  of  animals  poisoned, 
for  the  reason  that  it  grows  only  along  some  stream  or  around  a 
pond  where  they  come  to  drink.  In  such  cases  a  comparatively  small 
amount  of  digging  or  fencing  will  remove  the  danger.  Stock  should, 
in  any  case,  be  kept  away  from  marshy  areas  where  it  is  known  to  occur. 

Summary 

Water  hemlock  occurs  throughout  the  state  in  wet  ground  and 
along  streams,  but  not  in  sandy  or  stony  soils. 

All  parts  of  the  plant  are  poisonous,  but  the  roots  and  rootstocks 
are  most  virulent. 

Owing  to  the  rapidity  with  which  the  poison  takes  effect,  remedies 
are  of  little  avail.  Morphine  to  allay  the  pain  and  an  emetic  followed 
by  a  cathartic  are  among  the  suggested  remedies. 


BULLETIN  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA  225 

By  means  of  fencing  or  herding,  stock  should  be  kept  away  from 
areas  infested  by  this  plant. 

Eradication  by  digging  will  be  found  feasible  in  many  cases. 

DEATH   CAMAS    (Zygadenus   venenosus) 
(Liliaceae,  or  Lily  Family) 

Names. — This  plant  is  also  known  as  poison  camas,  poison  sego  lily, 
mystery-grass,  wild  onion,  and  lobelia,  but  none  of  these  names  are 
properly  applied  to  it.  Squirrel-food  and  hog  potato  are  additional 
local  names. 

Description. — Death  camas  is  an  erect  herb,  one  to  two  feet  high,  with 
slender  grass-like  leaves  from  near  the  base  and  bearing  later  in  the  season 
a  terminal  oblong  cluster  of  small  white  flowers.  It  grows  from  a  roundish 
bulb  one-half  to  one  and  one-half  inches  thick,  covered  with  thin  brown  coats; 
although  similar  in  appearance  to  that  of  the  wild  onion,  this  bulb  lacks  the 
peculiar  onion  odor.  The  lower  leaves  are  six  to  sixteen  inches  long  by  less 
than  one-half  inch  wide,  parallel-veined,  and  often  mistaken  for  grass  leaves 
but  without  the  ligule  and  joint  which  in  all  grasses  mark  the  junction 
between  blade  and  sheath.  The  individual  flowers,  scarcely  over  one-eighth 
inch  across,  are  borne  on  short  branches  of  the  cluster,  the  sepals  and  petals 
are  three  each  and  similar;  there  are  six  protruding  stamens,  and  a  three-celled 
ovary  which  matures  into  a  three-lobed  seed-pod. 

The  true  camas,  or  quamash  (Camassia  quamash  and  C.  leichtlinii) ,  the 
bulbs  of  which  are  eaten  by  the  Indians,  is  readily  distinguished  from  death 
camas  by  its  larger  bulb  and  larger  blue  flowers.  It  grows  in  very  wet  places, 
especially  in  the  mountains. 

Distribution  and  habitat. — This  plant  grows  in  all  of  the  Pacific 
States  and  is  especially  plentiful  in  the  northern  part  of  California. 
In  the  middle  and  southern  parts  of  the  state  it  is  restricted  to  the 
mountain  meadows  and  even  there  it  is  seldom  sufficiently  plentiful 
to  constitute  a  menace. 

Of  special  interest  to  stockmen  is  the  fact  that  death  camas  is 
very  exacting  in  the  matter  of  soil  and  moisture,  so  that  one  familiar 
with  its  requirements  can  predict  almost  to  a  certainty  whether  or 
not  it  will  be  found  in  a  given  meadow  the  conditions  of  which  are 
known.  It  always  grows  in  moist  soils,  but  never  in  marshy  or  wet 
places.  In  dry  meadows  it  is  therefore  restricted  to  the  swales  and 
ravines,  in  wet  meadows  to  the  higher  and  better  drained  portions  but 
it  never  grows  along  the  dry  meadow  borders.  Aside  from  meadows, 
the  plants  are  often  found  along  depressions  in  the  hills  where  the 
moisture  is  near  the  surface  but  these  belts  are  usually  too  narrow 
to  be  of  much  importance. 


226  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

Poisonous  characters. — All  parts  of  the  plant  are  poisonous  to  sheep 
but  the  leaves  cause  the  most  trouble  since  they  are  eaten  along  with 
grass  during  spring  months.  The  bulbs  are  dangerous  only  after 
rains,  since  at  other  times  it  is  almost  impossible  for  sheep  to  pull  them 
out  of  the  ground.  The  seeds  are  said  to  produce  poisoning  when  the 
mature  plants  are  cut  and  fed  with  hay  from  natural  meadows.  Hogs 
are  seldom  if  ever  poisoned  by  death  camas  but  on  the  contrary  seem 
to  thrive  on  it;  this  has  given  to  the  bulbs  the  name  of  "hog  potato." 
So  far  as  we  have  been  able  to  learn,  horses  and  cows  universally 
refuse  to  eat  death  camas. 

Symptoms. — The  symptoms  are  remarkably  uniform  and  character- 
istic so  that  stockmen  should  be  able  to  recognize  cases  of  poisoning 
by  this  plant.  According  to  Chesnut  and  Wilcox,  the  first  signs  of 
poisoning  are  a  certain  uneasiness  and  irregularity  in  the  movements 
of  the  sheep.  As  these  symptoms  become  more  pronounced  they  are 
accompanied  by  spasms  and  rapid  breathing.  An  increased  flow  of 
saliva  and  regurgitation  through  the  mouth  and  nostrils  nearly  always 
take  place.  The  later  symptoms  include  complete  motor  paralysis, 
combined  with  exceedingly  rapid  and  shallow  breathing  and  a  fre- 
quent weak  pulse.  Death  may  ensue  in  from  one  to  twelve  hours, 
depending  upon  the  amount  eaten.  It  often  happens  that  a  sheep 
will  become  paralyzed  and  lie  quietly  on  its  side  for  some  hours, 
after  which  it  will  slowly  recover,  but  there  is  little  hope  for  an  animal 
that  has  been  down  for  twenty-four  hours  or  longer.  The  lungs  become 
much  congested  and  while  the  brain  may  also  show  slight  congestion 
it  has  no  lesions. 

Remedies. — Permanganate  of  potash  and  aluminum  sulfate  admin- 
istered as  described  on  page  220  has  been  recommended  as  an  effective 
antidote  in  cases  of  poisoning  by  death  camas.  Chesnut  also  suggests, 
as  an  equally  good  remedy,  caffein  diuretin,  given  hypodermically 
or  even  through  the  mouth.  Caffein  diuretin  is  not  carried  in  stock 
by  most  druggists  but  could  be  ordered  in  advance  by  stockmen  where 
animals  are  likely  to  be  subject  to  poisoning  by  death  camas.  This 
remedy  is  not  so  easily  administered  as  permanganate  of  potash. 

Preventive  measures. — The  first  step  to  be  taken  in  prevention 
is  to  become  thoroughly  acquainted  with  the  plant,  in  order  that  it 
may  be  distinguished  from  harmless  species.  Its  habit  of  lurking  in 
the  meadows  where  it  is  eaten  along  with  grasses  makes  its  recognition 
by  stockmen  a  matter  of  prime  importance.  During  the  flowering 
period  it  may  be  known  at  a  glance  by  the  characteristic  cluster  of 
white  flowers  but  its  leaves  so  closely  simulate  those  of  certain  grasses 
that  it  is  not  so  easily  detected  in  its  younger  stages.     However,  the 


Bulletin  249 


STOCK  POISONING  PLANTS  OF  CALIFORNIA 


227 


Fig.  2.  Death  camas  (Zygadenus  venenosus).  One-half  natural 
size.  A  plant  of  moist  but  not  wet  soil,  occurring  chiefly  in  northern 
California.  The  leaves  are  the  parts  usually  eaten.  Sheep  are  the 
animals  most  often  poisoned. 


228  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

entire  absence  of  ligule  and  joint  between  blade  and  sheath  is  a 
reliable  distinguishing  character  since  these  are  present  in  all  grass 
leaves.  In  case  of  doubt  the  underground  parts  should  be  examined. 
No  California  grass  grows  from  true  bulbs.  Other  members  of  the 
lily  family  might  be  mistaken  for  death  camas  but  not  many  of  them 
grow  in  meadows,  except  certain  species  of  Brodiaea  and  these  may 
be  distinguished  by  the  solid  "bulb"  without  concentric  layers. 

Eradication  of  death  camas  from  the  range  is  rarely  practicable. 
Where  it  grows  at  all  the  plants  are  usually  so  numerous  and  their 
uprooting  so  laborious  that  this  method  is  far  too  expensive.  Eradica- 
tion is  feasible  only  where  the  species  grows  in  narrow  strips,  as 
along  shallow  ravines  in  the  mountains. 

A  better  policy  and  one  which  is  more  generally  followed  is  to 
fence  or  herd  stock  away  from  infested  areas  until  all  danger  of 
poisoning  is  over.  The  most  dangerous  period  is  in  the  early  spring 
when  the  grass  is  beginning  to  grow.  The  death  camas  sends  up  its 
leaves  somewhat  ahead  of  the  grass  but  they  also  dry  up  and  become 
harmless  before  the  grass  fully  matures.  Before  admitting  animals 
to  pastures  where  the  plant  grows  one  should  make  a  careful  examina- 
tion to  see  that  no  considerable  number  of  the  plants  are  still  in  a 
green  or  growing  condition. 

In  the  valley  meadows  of  northern  California  and  in  Owens  Valley 
the  plants  have  usually  passed  their  dangerous  condition  by  the  first 
or  middle  of  July.  On  the  mountain  ranges  it  may  be  as  late  as 
August,  in  southern  California  as  early  as  June.  But  it  must  be 
remembered  that  the  date  of  maturity  will  vary  with  season  as  well 
as  with  altitude,  slope,  etc.  and  that  the  condition  of  the  plants  can 
therefore  be  determined  only  by  a  personal  examination. 


Summary 

Death  camas  is  common  in  the  meadows  of  northern   California 
where  it  grows  in  moist  situations  but  not  in  wet  or  boggy  soil. 

While  all  parts  of  the  plant  produce  poisoning  the  leaves  are  the 
part  usually  eaten. 

Permanganate  of  potash  and  caffein   diuretin  have  been  recom- 
mended as  remedies. 

By  means  of  proper  fencing  or  herding  sheep  should  be  kept  away 
from  this  plant  in  the  springtime  and  until  its  green  parts  have 
dried  up. 

It  is  important  that  stockmen  should  be  able  to  distinguish  death 
camas  from  grasses  and  from  other  harmless  plants. 


BULLETIN  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA  229 

LARKSPURS   (Delphinium  species) 
(Ranunculaceae,  or  Buttercup  Family) 

Names. — Larkspurs  are  seldom  known  by  any  other  name,  although 
they  are  sometimes  called  "cow  poison,"  or  "poison  weed."  Robust 
leafy  species,  three  to  six  feet  high,  are  here  referred  to  as  tall 
larkspurs  (Delphinium  glaucum,  D.  calif ornicum,  and  their  allies). 
Under  low  larkspur  we  include  species  which  do  not  ordinarily 
exceed  two  feet  in  height  and  are  leafy  only  towards  the  base  (D. 
parryi,  D.  decorum,  etc.). 

Description. — The  tall  larkspurs  produce  many  erect  stems  forming  con- 
spicuous leafy  clumps  becoming  three  to  six  feet  high.  The  low  larkspurs 
have  solitary  or  few  stems  and  are  much  less  conspicuous. 
In  all  species  the  leaves  are  alternate  and  palmately 
divided  into  mostly  toothed  or  deeply  cut  segments.  The 
flowers  of  the  dangerous  kinds  are  some  shade  of  blue  or 
lavender  and  are  borne  in  terminal  erect  racemes.  The 
individual  flower  has  a  very  characteristic  shape  owing  to 
the  spur-like  backward  development  of  the  upper  sepal, 
as  shown  in  figure  4.  The  numerous  seeds  are  borne 
in  dry,  three-pointed  pods  one-fourth  to  three-fourths  of 
an  inch  long. 

Wild    geranium    is    sometimes    mistaken    for    larkspur 
(\  when    examined    before    the    flowers    appear,    but    it    can 

Fig.  3.  Leaf  of  always  be  distinguished  by  the  fact  that  the  leaves  bear 
Geranium  showing  two  small  appendages  known  as  stipules  at  the  base  of 
stipules.  One-third  the  petiole  or  leaf -stem  (see  fig.  3),  while  in  larkspur  the 
stipules  are  not  present.  Aconite,  or  monkshood,  is  some- 
times confused  with  tall  larkspur  with  which  it  often  grows,  but  the  upper 
leaves  are  more  numerous  and  nearly  sessile,  and  the  flowers  are  conspicuously 
hooded  instead  of  spurred. 

Distribution  and  habitat. — In  California  the  tall  larkspurs  are 
restricted  to  moist  meadows,  gulches,  and  borders  of  springs  or  ponds 
in  the  northern  part  of  the  state  and  the  Sierra  Nevada.  It  is  especi- 
ally plentiful  along  rivulets  and  moist  ravines  leading  into  mountain 
meadows.  Species  of  low  larkspur  also  occur  in  the  same  districts 
but  inhabit  only  open  hillsides,  sparsely  forested  areas,  and  similar 
situations  and  are  not  sufficiently  abundant  to  be  a  serious  menace. 
In  the  Coast  Kanges,  however,  and  especially  in  their  southern  por- 
tions, certain  species  of  low  larkspur  are  rather  abundant  and  serious 
losses  from  poisoning  are  reported.  The  plants  here  grow  on  open 
hillsides  and  in  openings  in  the  chaparral.  Here  their  green  tufts 
of  basal  leaves,  appearing  in  the  early  spring,  before  other  feed  is 
plentiful,  are  very  tempting  to  livestock. 


230  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

Poisonous  characters. — Probably  all  parts  of  the  plant  are  poison- 
ous except  the  flowers.  The  roots  are  rarely  eaten  and  so  are  of 
little  importance.  The  time  of  greatest  danger  from  these  plants  is 
while  the  young  leaves  and  stems  are  growing,  before  the  flowers 
appear.  After  the  flowering  period  the  plant  of  the  low  larkspur  very 
soon  withers  and  dries  up,  becoming  unattractive  to  stock,  while  in 
the  tall  larkspur  the  leaves  lose  their  poisonous  properties  as  the  plant 
matures.  It  is  therefore  of  the  utmost  importance  for  stockmen  to 
become  familiar  with  the  leaf  and  stem  characters  so  that  they  may 
recognize  the  plant  before  the  flowers  appear.  The  seeds  are  more 
poisonous  than  the  leaves  but  are  seldom  eaten  in  sufficient  quantity 
to  cause  trouble.  Larkspurs  are  particularly  dangerous  during  seas- 
ons when  there  is  a  scarcity  of  feed  either  through  overstocking  or 
drought.  Under  such  conditions  larkspur  may  become  the  most  con- 
spicuous form  of  vegetation  on  the  range  and  attract  animals 
accordingly.  i  i1 

Cattle  and  horses  are  the  animals  usually  killed  by  eating  these 
plants.     It  seems  probable  that  sheep  are  never  injured  by  them. 

Symptoms. — Usually  the  earlier  symptoms  of  larkspur  poisoning 
resemble  those  of  death  camas  very  closely.  In  both  cases  there  is  a 
marked  stiffness  of  the  muscles  and  a  certain  irregularity  in  the  gait. 
These  symptoms  become  more  pronounced  and  in  larkspur  poisoning 
the  animal  soon  falls,  often  very  suddenly,  "the  legs  appearing  to 
crumple  up  under  it."  The  skin  is  sensitive  to  the  touch  and  the 
muscles  of  the  sides  quiver.  The  special  senses,  however,  are  not 
impaired.  The  later  stages  of  poisoning  by  larkspur  are  character- 
ized by  violent  kicking  and  attempts  to  rise  but  "it  can  hardly  be 
said  that  the  poison  produces  convulsions"  (Marsh).  This  activity 
on  the  part  of  the  animal  constitutes  a  distinguishing  feature  be- 
tween poisoning  by  death  camas  and  larkspur.  In  cases  of  poisoning 
by  death  camas  the  animal  usually  lies  in  a  stupefied  condition 
during  the  later  stages,  convulsions  being  entirely  absent. 

Autopsies  of  animals  poisoned  by  larkspur  show  inflammation  of 
the  stomach,  small  intestine,  and  windpipe,  and  congestion  of  the 
surface  blood  vessels.     The  kidneys  are  usually  much  congested. 

Remedies. — In  mild  cases  the  animal  will  recover  if  congestion  is 
relieved  by  the  simple  expedient  of  turning  the  body  so  that  the  head 
will  be  higher  than  the  other  parts.  The  animal  should  then  be  allowed 
to  rest  quietly.  The  following  formula  has  been  used  as  a  subcutan- 
eous injection  with  very  beneficial  results  and  is  especially  recom- 
mended by  Marsh  to  those  accustomed  to  the  use  of  a  hypodermic 
syringe. 


Bulletin  249         STOCK  POISONING  PLANTS  OF  CALIFORNIA 


231 


Fig.  4.  Tall  mountain  larkspur  (Delphinium  glaucum).  One-half 
natural  size.  A  type  of  our  tall  larkspurs,  which  are  plants  of  moist 
ground  in  the  mountains.  Low  larkspurs  grow  in  more  open  places. 
All  parts  of  the  plant  except  the  flowers  are  poisonous. 


232  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 

Physostigmin  salicylate,  one  grain. 

Pilocarpin  hydrochlorid,  two  grains. 

Strychnin  sulfate,  one-half  grain. 

These  quantities  are  for  an  animal  weighing  five  hundred  or  six 
hundred  pounds.  This  remedy  relieves  constipation  and  stimulates 
respiration.    The  dose  should  not  be  repeated. 

Preventive  measures. — Eradication  of  larkspurs  from  the  range 
is  not  practicable,  since  the  plants  are  usually  so  numerous  where 
they  occur  that  uprooting  would  be  far  too  expensive.  It  is  feasible 
only  in  small  pastures  or  when  the  plants  form  dense  stands  on  small 
areas.  A  better  policy  is  to  fence  or  herd  stock  away  from  the  infested 
areas  until  the  flowering  period  has  passed.  This  procedure  will 
occasion  little  loss  since  the  forage  on  the  area  may  be  utilized  later 
in  the  season. 

It  should  be  remembered  that  small  amounts  of  larkspur  are  not 
fatal  and  that  if  other  feed  is  plentiful  there  is  no  danger  in  admitting 
animals  to  ranges  where  it  grows.  Kanges  where  cattle  and  horses 
could  not  be  grazed  may  be  profitably  turned  over  to  sheep,  since 
they  are  seldom  if  ever  injured  by  larkspur. 

Summary 

The  young  leaves  and  stems  are  usually  the  parts  of  larkspur 
plants  which  cause  poisoning. 

Perhaps  all  of  our  California  species  of  larkspur  are  poisonous 
but  many  of  them  do  not  grow  in  sufficient  abundance  to  constitute 
a  menace. 

It  is  important  that  stockmen  should  distinguish  between  lark- 
spur and  similar  plants,  especially  aconite  and  wild  geranium. 

By  means  of  proper  fencing  or  herding,  stock  should  be  kept 
away  from  these  plants  until  the  green  parts  have  dried  up. 

Sheep  may  be  safely  admitted  to  ranges  where  severe  losses  would 
result  from  the  grazing  of  cattle  or  horses. 

Poisoned  animals  should  be  permitted  to  remain  as  quiet  as 
possible  and  the  body  should  be  turned  so  that  the  head  is  higher 
than  the  other  parts. 

MILKWEEDS   (Asclepias  species) 
(Asclepiadaceae,  or  Milkweed  Family) 

Names. — These  plants  are  generally  known  by  the  name  of  milk- 
weed. Descriptive  terms  are  added  to  designate  the  various  species, 
since  there  are  nine  kinds  more  or  less  common  in  California.    Among 


BULLETIN  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA 


233 


Fig.  5.  Narrow-leaf  milkweed  (Asclepias  mexicana).  Other  milkweeds 
have  broader  leaves.  Milkweeds  grow  in  dry  soil.  The  leaves  and  stems 
contain  the  poison.    Sheep  are  the  animals  usually  poisoned  by  milkweeds. 


234  UNIVERSITY   OF    CALIFORNIA — EXPERIMENT    STATION 

the  most  important  of  these  are  the  narrow-leaf  milkweed  {Asclepias 
mexicana),  the  woolly-pod  milkweed  (A.  eriocarpa)  and,  in  the 
mountains,  the  showy  milkweed  (  A.  speciosa).  Not  all  plants  with 
a  milky  juice  are  milkweeds  in  the  true  sense.  For  example,  both 
sow  thistle  and  prickly  lettuce  have  a  milky  juice,  yet  neither  is 
dangerous  to  stock;  both  have  the  leaves  alternately  arranged  on 
the  stem  and  are  thus  distinguished  at  a  glance  from  the  true  milk- 
weeds. 

Description. — The  milkweeds  are  erect  herbs  with  a  milky  juice  and  grow 
one  and  one-half  to  five  feet  high  from  thick  perennial  roots.  The  leaves 
are  opposite  or  in  whorls  of  three  or  four  and  both  leaves  and  stems  are 
usually  more  or  less  woolly.  In  narrow-leaf  milkweed,  the  species  figured  on 
page  233,  the  leaves  are  smooth  (without  wool)  and  narrower  than  in  most 
of  our  other  species.  The  flowers  are  borne  in  umbels  variously  arranged 
near  the  summit  of  the  stem;  they  are  usually  some  shade  of  pink  or  white 
and  are  quite  characteristic  in  shape.  The  parts  of  the  flower  are  in  fives. 
The  fruit  is  a  pod  containing  numerous  seeds,  each  of  which  has  a  silky  tuft 
of  hairs  at  the  end. 

Distribution  and  habitat. — Milkweeds  are  inhabitants  of  dry  and 
poor  soil,  often  growing  in  dry  stony  stream  beds,  along  waysides 
or  railway  embankments,  or  on  exposed  gravelly  slopes.  They  range 
throughout  the  state  at  low  altitudes  and  one  species,  the  showy 
milkweed,  is  found  in  the  Sierra  Nevada  up  to  seven  thousand  feet 
altitude,  growing  in  the  drier  parts  of  meadows  where  it  is  perhaps 
never  eaten. 

Poisonous  characters. — The  leaves  and  stems  of  the  milkweed  are 
poisonous.  So  far  as  we  are  able  to  learn,  horses  and  cattle  seldom 
eat  the  plants,  but  sheep  are  sometimes  poisoned.  When  feeding  free 
on  the  range  even  sheep  are  in  but  little  danger  of  milkweed  poisoning, 
but  when  driven  for  long  distances  over  territory  where  food  and 
water  are  scarce  they  are  often  attracted  to  these  rather  succulent 
herbs.     Late  summer  and  autumn  are  the  seasons  of  greatest  danger. 

Symptoms. — No  detailed  study  has  been  made  of  the  symptoms  of 
milkweed  poisoning  but  the  following  description  has  been  drawn 
from  the  observations  of  shepherds.  Soon  after  eating,  the  sheep 
falls  behind  the  rest  of  the  band,  then  stops  and  walks  backward  a 
short  distance.  This  is  said  to  be  the  most  characteristic  symptom. 
The  effect  of  the  poison  seems  to  be  to  stupefy  the  animal,  for  even 
the  wildest  will  not  run  away  when  approached.  The  sheep  may 
stand  still  for  some  time,  occasionally  lying  down  and  rising  again. 
The  muscles  of  the  sides  and  flanks  tremble,  the  eyes  are  glassy,  and 
there  is  usually  some  frothing  at  the  mouth.  The  duration  of  the 
symptoms  is  from  one  to  six  hours. 


Bulletin  249         STOCK  POISONING  PLANTS  OF  CALIFORNIA  235 

Remedies. — It  is  probable  that  the  permanganate  of  potash  remedy 
would  be  effective  and  is  worthy  of  trial.  So  far  as  we  can  find,  it  has 
not  been  used  in  cases  of  milkweed  poisoning. 

Preventive  measures. — No  especial  precautions  are  required  against 
these  plants  while  sheep  are  grazing  at  will  on  a  range.  During  long 
drives  it  is  advisable  to  send  a  man  ahead  to  locate  large  patches  of 
the  plants  in  order  that  the  band  may  be  driven  around  them  and 
to  cut  down  any  scattering  milkweeds  along  the  route.  These  simple 
methods,  already  employed  by  many  practical  sheepmen,  should  be 
more  generally  followed,  since  their  universal  use  would  practically 
eliminate  milkweed  from  the  list  of  dangerous  plants. 

Summary 

Milkweeds  are  common  on  the  dry  hills  and  plains  throughout 
the  state. 

The  leaves  and  stems  are  poisonous. 

Milkweeds  are  especially  dangerous  to  sheep  when  driven  across 
dry  barren  country. 

Permanganate  of  potash  will  probably  be  found  an  effective  remedy. 

Milkweeds  growing  on  a  route  taken  by  sheep  across  country 
should  be  cut  down  or  the  band  should  be  driven  around  them. 

LUPINES   (Lupinus  species) 
(Leguminosae,  or  Pea  Family) 

Names. — In  California  the  various  species  of  lupine  are  some- 
times known  as  blue  pea,  wild  pea,  pea  vine,  and  even  wild  bean,  but 
all  of  these  names  are  erroneous.  Although  we  have  many  pea-like 
and  bean-like  native  plants,  the  lupines  may  be  distinguished  from 
most  of  these  by  the  leaf  characters  as  pointed  out  below. 

Description. — The  lupines  are  annual  and  perennial  herbs  or  low  shrubs 
belonging  to  the  pea  family.  The  leaves  are  long  stemmed  and  divided  into 
from  four  to  fifteen  leaflets  radiating  from  the  summit  of  the  common  leaf- 
stalk. The  plant  illustrated  is  fairly  typical  of  all  our  species,  any  of  which 
should  be  recognized  from  the  figure.  The  flowers  are  borne  in  long  terminal 
racemes  or  spikes  and  are  quite  showy  taken  together,  though  singly  they 
are  rather  small.  In  different  species  the  flowers  may  be  blue,  white,  yellow, 
or  pink;  in  general  structure  they  resemble  those  of  the  common  bean  or  pea. 
The  fruit  is  a  pod  similar  to  that  of  the  pea  and  contains  two  or  more 
small  seeds. 

Distribution  and  habitat. — No  portion  of  California  is  entirely 
free  from  lupines  except  the  cultivated  districts,  the  swamps,  and 
some  portions   of  the   desert  area.     Nearly   all   cases   of   poisoning, 


236  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

however,  occur  in  the  northern  part  of  the  state  where  the  plants 
are  used  to  some  extent  for  hay. 

Poisonous  characters. — Several  of  our  species  of  lupine  are  known 
to  be  poisonous  to  stock  and  it  is  quite  probable  that  many  more  will 
be  found  to  be  more  or  less  injurious.  As  far  as  present  investiga- 
tions go  the  seeds  are  the  only  part  of  the  plant  positively  known  to 
be  poisonous,  although  the  green  herbage,  as  in  other  members  of  the 
same  family  cause  bloat  if  eaten  in  large  quantities,  especially  when 
it  is  wet  or  when  eaten  by  animals  just  in  from  a  dry  range  or  when 
hot  or  very  hungry.  Lupines  are  often  fed  as  hay  with  no  ill  effects 
if  gathered  either  before  the  seeds  have  matured  or  after  they  have 
fallen  from  the  pod.  Sometimes  stock  have  been  poisoned  by  lupine 
fed  under  apparently  the  same  conditions  as  in  preceding  years 
when  no  ill  effects  followed.  But  in  every  case  of  poisoning  it  was 
found  that  the  hay  had  been  cut  after  the  poisonous  principle  had 
formed  in  the  seeds  and  before  these  had  fully  matured  and  shattered 
out.  Lupines,  therefore,  should  never  be  fed  nor  cut  for  hay  while 
mature  or  nearly  mature  seed  is  in  the  pod,  unless  it  has  been  posi- 
tively proved  that  the  species  used  is  not  poisonous.  Even  when  not 
in  seed  great  caution  should  be  exercised  in  the  use  of  lupine  hay. 

Symptoms.— The  symptoms  caused  by  lupine  poisoning  are  rather 
definite  and  have  given  rise  to  the  term  lupinosis.  In  Europe  two 
forms  of  lupine  poisoning  are  recognized,  an  acute  and  a  chronic  form. 
In  the  United  States,  so  far,  only  the  acute  form  has  been  recognized. 

Prom  the  beginning  there  is  an  acute  cerebral  congestion  accomp- 
anied by  great  mental  excitement.  The  animals  appear  crazed  and 
rush  about  in  all  directions  butting  into  each  other  and  other  objects. 
This  first  stage  of  frenzy  is  followed  by  a  second  characterized  by 
irregularity  of  movement,  violent  spasms,  and  falling  fits,  increasing 
in  severity  until  finally  collapse  occurs.  When  the  animal  is  unable 
to  stand,  convulsions  follow  each  other  at  short  intervals.  Death 
usually  occurs  within  one-half  to  one  and  one-half  hours  after  the 
first  symptoms,  although  animals  may  sometimes  linger  on  for  a  day 
or  so.  During  the  attack  the  pulse  is  strong  and  irregular,  there  is 
often  frothing  at  the  mouth,  the  flow  of  urine  is  increased  and  this 
is  sometimes  bloody.  The  lungs  and  cerebral  membranes  are  congested 
and  in  more  violent  cases  small  blood  vessels  are  found  ruptured 
in  various  parts  of  the  body. 

Remedies. — The  permanganate  of  potash  remedy  is  recommended 
for  cases  of  poisoning  by  lupine,  but  it  must  be  administered  very 
early  in  the  attack  to  be  effective.  By  the  rapidity  with  which  the 
symptoms  appear  it  is  evident  that  enough  of  the  toxic  substance 


Bulletin  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA 


237 


Fig.  6.  Lupine  (Lupinus  leucophyllus) .  One-half  natural  size. 
Lupines  occur  throughout  the  state  except  in  swamps.  Most  cases  of 
poisoning  occur  in  northern  California.  Only  the  seeds  are  poisonous. 
All  classes  of  stock  are  poisoned. 


238  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 

to  cause  death  enters  the  general  circulation  very  soon  after  the  seed 
has  been  eaten.  Acids  are  also  recommended  for  lupine  poisoning. 
For  this  purpose  acetic  acid  or  very  dilute  sulfuric  acid  is  suitable. 
Since  vinegar  contains  acetic  acid  its  use  would  be  beneficial.  Alkalies 
should  be  avoided. 

Preventive  measures. — The  eradication  of  lupine  is  impractical 
but  much  can  be  accomplished  by  keeping  stock  away  from  these 
plants  when  they  are  maturing  their  seed,  and  hay  containing  lupine 
seed  should  be  discarded.  As  a  prevention  against  bloat  animals  should 
not  be  turned  into  a  field  of  lupines  which  are  wet  or  while  the 
animals  are  exceedingly  hungry.  Animals  gradually  become  immune 
to  this  bloating  effect  of  lupine. 

Summary 

Lupines  are  very  abundant  in  California  and  are  often  cut  for 
hay  in  the  northern  part  of  the  state. 

The  seeds  are  the  most  dangerous  part  of  the  plant  though  bloat 
may  be  caused  by  feeding  upon  the  green  herbage. 

Lupines  should  never  be  fed  to  stock  while  the  pods  contain 
mature  or  nearly  mature  seed. 

The  recommended  remedies  include  permanganate  of  potash  and 
weak  acids. 

To  prevent  bloat  stock  should  not  be  allowed  to  feed  upon  green 
lupine  when  wet  or  if  the  animals  are  very  hungry  or  are  not 
accustomed  to  the  range. 

LOCO-WEEDS    (Astragalus    species) 
(Leguminosae,  or  Pea  Family) 

Names. — The  term  "loco-weed"  is  applied  to  any  species  of  As- 
tragalus suspected  of  causing  the  loco  disease.  The  sorts  with  blad- 
dery-inflated pods  are  often  known  as  rattle  weeds.  Some  of  the 
most  dangerous  species  belong  to  the  section  of  Astragalus  known 
as  Aragallus,  considered  by  some  botanists  to  be  a  distinct  genus. 

Description. — The  loco-weeds  are  annual  and  perennial  herbs  belonging  to 
the  pea  family,  with  odd-pinnate  leaves.  The  purple,  white,  or  pale-yellow 
flowers  resemble  those  of  the  common  bean  in  shape  but  are  of  smaller  size 
and  are  borne  in  crowded  racemes,  spikes,  or  heads.  The  fruit  is  probably 
the  most  characteristic  feature  of  these  plants;  it  is  a  pod  containing  from 
two  to  many  small  seeds  and  is  commonly  turgid  or  inflated  and  bladder-like. 
There  are  many  species  of  Astragalus  in  California  but  all  are  quite  similar 
in  structure,  so  there  should  be  little  difficulty  in  recognizing  any  of  them 
after  a  study  of  the  figure  of  Astragalus  hornii  on  page  239;  it  must  be  re- 
membered, however,  that  they  vary  much  in  size  and  in  the  shape  of  the  pod. 


Bulletin  249  STOCK  POISONING  PLANTS  OP  CALIFORNIA 


239 


Fig.  7.  Loco-weed  (Astragalus  hornii).  One-half  natural 
size.  One  type  of  our  California  species  of  loco-weeds,  which 
are  found  throughout  the  state  except  in  moist  places.  Sheep 
and  horses  are  the  animals  commonly  affected;  cattle  rarely. 


240  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

Distribution  and  habitat. — These  plants  are  much  too  common 
in  all  of  our  western  states,  ranging  from  sea  level  nearly  to  the 
summits  of  our  highest  peaks.  They  do  not  grow  in  meadows  but 
often  inhabit  meadow  borders  and  are  abundant  on  many  of  the 
plains  and  upland  ranges. 

Poisonous  characters. — Notwithstanding  the  large  amount  of  study 
that  has  been  given  to  the  loco  disease,  the  principle  which  causes 
it  is  as  yet  unknown.  For  a  time  the  injurious  effect  was  thought 
to  be  due  to  barium  but  recent  investigations  have  overthrown  this 
theory.  We  are  unable  to  give  a  list  of  the  species  of  Astragalus 
which  are  harmful,  so  that  for  the  present  practically  all  of  them  must 
be  regarded  with  suspicion.  Cases  of  loco  poisoning  are  much  less 
common  in  California  than  in  the  Rocky  Mountain  states  and  it  is 
possible  that  only  a  few  of  the  kinds  growing  here  are  really  injurious. 

The  poisonous  substance,  whatever  it  may  be,  acts  as  a  slow  poison, 
affecting  primarily  the  nervous  system  and  resembling  in  its  effect 
that  of  drug  habits  in  man  rather  than  of  the  other  plant  poisons 
we  have  been  considering.  A  peculiarity  of  the  disease  is  that  while 
animals  do  not  at  first  readily  eat  the  weed,  yet  having  once  become 
addicted  to  the  habit,  they  will  seek  the  loco-weed  and  feed  upon  it 
to  the  partial  or  complete  exclusion  of  other  plants.  This  ' '  loco-habit ' ' 
is  often  formed  through  imitating  other  animals  or  because  of  the 
scarcity  of  better  food.  Owners  of  stock  in  infested  districts  should 
therefore  appreciate  the  importance  of  keeping  animals  well  supplied 
with  proper  food  and  of  immediately  removing  from  the  band  or 
herd  any  individual  that  has  acquired  the  habit.  There  seems  to  be 
some  relation  between  the  loco  habit  and  the  salting  of  stock.  Chesnut 
states  that  sheep  are  more  likely  to  form  the  loco  habit  when  deprived 
of  salt  and  that  the  eating  of  alkali  seems  to  create  a  perverted 
appetite  which  leads  animals  to  feed  upon  loco-weeds. 

Horses  and  sheep  are  the  animals  most  commonly  addicted  to 
the  loco  habit.  Cattle  eat  the  weed  but  rarely.  Colts  and  lambs  are 
far  more  likely  to  acquire  the  habit  than  are  adult  horses  and  sheep. 

Symptoms. — Usually  the  first  symptom  of  loco  poisoning  is  a 
change  in  the  general  condition  of  the  animal.  It  becomes  stupid, 
is  prone  to  wander  away  from  the  herd,  and  becomes  emaciated, 
dejected,  and  untidy  in  appearance.  The  derangement  of  the  nervous 
system  makes  itself  evident  in  the  incoordination  of  the  muscular 
movements  or  through  errors  in  judgment  of  the  size  and  shape  of 
objects.  Irregularity  in  gait  is  noted  and  the  animal  drags  its  feet 
more  or  less,  this  being  particularly  noticeable  in  the  hind  legs.     The 


Bulletin  249         STOCK  POISONING  PLANTS  OF  CALIFORNIA  241 

muscular  incoordination  may  first  appear  simply  in  the  peculiarly 
extended  or  otherwise  unnatural  position  in  which  the  animal  carries 
its  head.  Sometimes  the  animal  becomes  frightened  from  no  apparent 
reason.  Locoed  horses  used  for  draft  or  driving  purposes  frequently 
run  away  or  indulge  in  spells  of  kicking  without  apparent  reason. 
The  sight  and  also  the  hearing  may  be  affected,  especially  in  acute 
cases.  Horses  lose  the  power  of  locomotion  to  a  large  degree  during 
the  later  stages  of  the  disease  and  will  remain  for  long  periods  upon 
a  small  area  of  ground,  seldom  or  never  lying  down  and  finally  die 
of  starvation. 

In  post  mortem  examination  of  locoed  animals  accumulations 
of  coagulated  serum  in  a  gelatinous  form  are  found  in  various  parts 
of  the  body,  particularly  about  the  heart  and  in  the  cavity  of  the  spinal 
column.  The  nervous  system  is  more  fully  supplied  with  blood  than 
when  the  animal  is  in  a  normal  condition.  The  walls  of  the  stomach 
are  frequently  inflamed  and  it  is  common  to  find  ulcers  in  the  pyloric 
end  of  the  stomach  of  horses  and  in  the  fourth  stomach  of  cattle 
and  sheep. 

Remedies. — At  present  no  specific  antidote  is  known  for  loco  pois- 
oning. In  experimental  work  carried  on  in  Colorado,  by  Dr.  C.  D wight 
Marsh  of  the  United  States  Department  of  Agriculture,  and  his  asso- 
ciates, it  was  found  possible  to  bring  most  animals  out  of  the  locoed 
condition  if  they  were  worth  enough  to  warrant  a  rather  extended 
course  of  treatment.  The  following  directions  are  based  on  Dr.  Marsh's 
results.     (See  Farmers'  Bulletin  380.) 

Many  animals,  during  the  early  stages  of  the  disease,  can  be  cured 
by  simply  taking  them  away  from  the  loco- weed  and  feeding  them 
upon  nutritious  food.  It  is  very  important  that  this  should  have 
laxative  properties,  as  locoed  animals  are  always  constipated.  Green 
alfalfa  is  especially  suitable,  or  oil  meal  may  be  mixed  with  the  grain 
in  case  this  is  being  fed.  It  is  sometimes  desirable  to  give  epsom  salts 
to  relieve  this  constipated  condition,  the  dose  for  cattle  being  about 
one  pound,  for  calves  two  ounces,  for  horses  eight  ounces,  and  for 
full-grown  sheep  four  ounces.  These  doses  should  be  given  as  a 
drench  and  varied  according  to  the  size  and  condition  of  the  individual. 
It  is  usually  not  necessary  to  repeat  the  dose  many  times  if  the  feed 
is  of  a  laxative  character. 

To  relieve  the  nervous  condition,  Fowler's  solution  gives  the  best 
result  in  the  case  of  horses.  This  is  given,  usually  for  a  month,  in 
daily  doses  of  four  to  six  drams  with  the  grain  or  in  drinking  water. 
Strychnin  is  recommended  for  cattle.  It  should  be  given  hypo- 
dermically  in  very  small  doses  of  three-twentieths  to  four-twentieths 


242  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

of  a  grain,  continuing  for  about  thirty  days.  Emphasis  should  be 
placed  upon  the  importance  of  giving  only  small  doses  of  strychnin 
as  locoed  animals  are  easily  killed  by  the  ordinary  amounts  admin- 
istered for  other  diseases.  In  the  case  of  sheep  it  will  usually  be  the 
best  policy  to  simply  remove  them  from  the  band  as  soon  as  they  show 
symptoms  of  loco  poisoning  and  feed  them  upon  nutritious  food  until 
fattened  for  market.  Any  animals  which  do  not  respond  to  this  treat- 
ment after  a  reasonable  time  may  as  well  be  killed,  as  their  only  value 
is  for  the  pelt. 

Preventive  measures. — Though  it  may  be  impossible  to  keep  stock 
away  from  loco-weeds  altogether,  an  effort  should  be  made  to  keep 
at  least  young  animals  off  a  range  where  the  poisonous  kinds  are 
known  to  grow,  especially  where  there  is  a  shortage  of  other  feed. 
Animals  addicted  to  the  habit  should  be  immediately  removed  from 
the  band  and  placed  in  a  pasture  free  from  loco-weed  or  fattened  for 
market.  In  the  case  of  horses,  although  they  may  be  kept  away  from 
loco-weed  and  appear  to  completely  recover,  they  will  sometimes  show 
the  effect  of  the  loco-weed  in  various  vicious  habits,  such  as  kicking 
or  running  away  without  apparent  cause. 

It  will  often  be  found  practicable  to  eradicate  these  plants  from 
the  range.  Since  they  are  usually  rather  scattered  or  only  in  small 
patches,  it  takes  much  less  labor  than  might  be  expected  to  clear  them 
from  a  pasture.  If  the  plants  are  cut  off  just  below  the  crown  of 
buds  they  will  not  grow  again.  It  is  advisable  to  kill  them  while  in 
flower  so  that  they  will  not  mature  the  season's  crop  of  seeds.  The 
seeds  live  for  several  years  and  do  not  all  germinate  in  any  one 
season,  so  the  area  will  have  to  be  gone  over  a  number  of  times  before 
the  weed  is  completely  killed  out. 

Summary 

Loco-weeds  belong  to  a  genus  of  plants  very  common  in  California, 
but  cases  of  poisoning  are  rare,  perhaps  because  most  species  are 
not  injurious,  or  because  they  are  harmful  only  under  certain  unusual 
conditions. 

Eating  of  loco-weeds  is  a  habit  formed  especially  by  young  animals, 
and  by  adults  when  other  food  is  scarce.  The  habit  is  learned  by  one 
animal  from  another. 

Locoed  animals  should  be  immediately  segregated  and  supplied 
with  nutritious  food  of  a  laxative  nature. 

Fowler's  solution  for  horses,  and  strychnin  for  cattle  is  recom- 
mended. 


Bulletin  249         STOCK  POISONING  PLANTS  OF  CALIFORNIA  243 

Eradication  of  loco-weed  from  the  range  is  sometimes  practicable. 
Special  attention  is  called  to  Farmers'  Bulletin  380  for  further 
information. 

POISONOUS   PLANTS    OF   MINOR    IMPORTANCE 

In  addition  to  the  foregoing  species  there  is  a  considerable  list 
of  California  plants  which  may,  under  certain  conditions,  be  more 
or  less  dangerous  to  domestic  animals.  Some  of  these  are  seldom 
eaten,  because  of  their  repulsive  taste  or  smell ;  others  grow  in  districts 
where  stock  rarely  graze ;  and  still  others  are  poisonous  for  only  short 
periods,  or  the  poison  is  not  sufficiently  virulent  to  cause  death.  From 
this  list,  the  following  may  be  selected  as  of  greatest  importance. 

Sorghum,  Kafir  Corn,  and  Johnson-grass  (Andropogon  species). 
Grass  Family. — These  well  known  agricultural  plants  are  not  native 
to  California,  but  since  under  unusual  conditions  they  may  become 
very  poisonous  to  stock  and  because  of  their  great  importance  to  the 
farmers  of  the  state,  they  are  considered  in  this  place.  Hot  dry 
weather  which  arrests  the  growth,  seems  to  favor  the  formation  of 
prussic  acid,  which  is  a  deadly  poison.  Stunted  plants  should  there- 
fore not  be  fed  to  stock.  Young  sorghum  contains  more  poison  than 
do  the  older  plants  and  hence  it  is  best  not  to  pasture  sorghum  until 
it  has  nearly  reached  maturity.  The  prussic  acid  is  said  to  disappear 
in  drying  so  that  when  cured  the  plants  may  be  fed  with  but  little 
danger  of  poisoning.  However,  all  plants  belonging  to  the  sorghum 
group  should  be  fed  with  caution  to  animals  which  have  fasted  for 
some  time. 

Prussic  acid  exerts  a  depressing  effect  on  the  heart.  The  symp- 
toms are  drowsiness,  twitching  of  the  muscles,  numbness  of  the  limbs, 
a  staggering  gait,  and  weakness  so  that  the  animal  is  unable  to  stand. 
It  combines  with  certain  carbohydrates  to  produce  compounds  which 
are  much  less  poisonous  to  the  animal  than  is  the  free  acid.  Except 
in  the  later  stages  of  poisoning,  a  strong  solution  of  glucose,  or 
"corn  syrup,"  or  molasses  is  said  to  be  beneficial.  Large  quantities 
of  milk  have  been  administered  with  good  results.  The  animal  should 
always  have  as  much  fresh  air  as  possible. 

California  False  Hellebore  (Veratrum  calif ornicum).  Lily  Fam- 
ily.— Most  mountaineers  know  this  plant  by  the  erroneous  name  of 
"skunk  cabbage."  It  is  a  coarse  perennial  with  broad  sessile  leaves 
and  grows  in  moist  places  in  the  mountain  districts.  Sheep  sometimes 
browse  on  the  foliage  with  impunity  and  there  is  much  doubt  as  to 
the  conditions  under  which  the  plant  is  poisonous.     Symptoms  of 


244  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

hellebore  poisoning  include  salivation,  burning  in  the  throat,  weak 
pulse,  and  labored  respiration.  Stimulants,  tannic  acid,  and  perman- 
ganate of  potash  have  been  recommended.  The  liberal  use  of  lard 
and  soda  has  sometimes  proved  effective  in  overcoming  the  ill  effects 
of  the  weed. 

Turkey  Mullein  (Eremocarpus  setigerus).  Spurge  Family. — 
Sheep  are  sometimes  killed  in  late  summer  and  autumn  by  this  weed. 
It  is  a  low,  grayish  annual,  forming  leafy  mats,  and  is  densely  stiff- 
hairy  throughout.  When  sheep  eat  the  plants,  as  they  sometimes  do 
when  better  forage  is  not  available,  the  branched  hairs  of  the  stems 
and  leaves  form  into  solid,  indigestible  balls  in  the  alimentary  tract. 
More  than  twenty  of  these  balls,  each  the  size  of  a  hickory -nut,  have 
been  taken  from  the  stomach  of  a  single  sheep.  Belgian  hares  have 
also  been  killed  by  feeding  on  turkey  mullein. 

Western  Choke-cherry  {Primus  demissa).  Rose  Family. — This 
well-known  shrub  or  small  tree  is  common  in  the  foothills  and  mount- 
tains  where  its  foliage  is  sometimes  browsed  upon  with  disastrous 
results.  Care  should  be  taken  to  see  that  animals  driven  across 
territory  where  choke-cherry  grows  are  supplied  with  other  feed.  A 
simple  expedient  when  several  bands  are  to  be  taken  to  the  same  feed- 
ing ground  is  to  route  them  by  different  trails  so  that  each  band  will 
be  supplied  with  harmless  forage  and  not  tempted  to  eat  choke-cherry 
leaves.  The  poisonous  principle  is  hydrocyanic  (prussic)  acid,  which 
exerts  a  depressing  action  on  the  heart.  Poisoned  animals  should  be 
given  a  stimulant,  for  example  alcohol,  atropine,  or  inhalations  of 
ammonia.    Lard  helps  to  prevent  absorption  of  the  poison. 

Poison  Hemlock  (Conium  maculatum).  Parsley  Family. — The 
flowers  and  fruit  of  poison  hemlock  resemble  those  of  water  hemlock 
but  the  tall  stems  grow  from  taproots  and  the  leaves  are  much  more 
finely  dissected.  The  plant  grows  almost  throughout  the  state  but  is 
quite  generally  avoided  by  stock,  perhaps  because,  of  its  disagreeable 
odor. 

Pale  Laurel  (Kalmia  poli folia).  Heath  Family. — This  low-spread- 
ing shrub  with  very  smooth  opposite  leaves  and  lilac-purple  flowers 
grows  in  moist  places  in  the  North  Coast  Ranges  and  Sierra  Nevada. 
It  is  one  of  our  most  poisonous  plants  but  fortunately  grows  in 
districts  where  there  is  but  little  stock-raising.  Fat  of  any  sort,  if 
given  in  the  early  stages  of  poisoning,  is  beneficial  and  permanganate 
of  potash  will  probably  be  found  effective. 

California  Buckeye  (Aesculus  calif ornica).  Buckeye  Family. — 
The  buckeye,  or  horse  chestnut,  is  too  well  known  to  call  for  a  des- 


BULLETIN  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA  245 

cription.  Its  leaves  and  fruits  are  reputed  to  be  poisonous  to  cattle, 
at  least  during  certain  seasons  of  the  year.  The  fruit  is  washed  and 
boiled  or  roasted  by  the  Indians,  who  then  eat  it  without  ill  effects. 

Nightshade  (Solanum  species).  Nightshade  Family. — The  night- 
shades are  spreading  herbs  with  alternate  ovate  stalked  leaves  and 
small  clusters  of  white  or  blue  flowers  followed-  by  globose  green  or 
black  berries.  The  amount  of  poison  present  varies  greatly  with 
growth.  The  herbage  and  green  berries  are  perhaps  always  more  or 
less  poisonous  but  the  ripe  berries,  especially  if  cooked,  are  harmless. 
The  fruits  of  some  varieties  of  nightshade  are  used  in  the  making 
of  pies  and  sauces  but  they  are  not  picked  until  ripe.  On  the  other 
hand,  the  green  berries  of  the  blue-flowered  species  have  been  known 
to  kill  children  who  had  eaten  them  in  play.  Any  of  the  domestic 
animals  may  be  poisoned  by  nightshade.  Practical  experience  has 
not  yet  indicated  the  best  remedy  for  nightshade  poisoning  but  in 
the  case  of  man  emetics  or  the  stomach  pump  should  be  resorted  to. 

Thorn  Apples  (Datura  meteloides,  D.  tatula,  and  D.  stramonium) . 
Nightshade  Family. — These  coarse,  rank-smelling  herbs  are  well  known. 
Animals  are  not  often  poisoned  but  children  sometimes  eat  the  seeds, 
which  are  especially  virulent.  The  recommended  treatment,  when 
human  beings  are  poisoned,  consists  of  the  use  of  the  stomach  pump 
(or  an  emetic),  heart  stimulants  and  the  application  of  external  heat 
and  artificial  respiration  if  necessary. 

Poison-oak  (Rhus  diversiloba).  Sumach  Family. — This  is  not  a 
stock  poisoning  plant  and  is  mentioned  here  only  because  of  its  popular 
interest.  In  some  parts  of  the  state  it  is  a  valuable  shrub  for  browsing 
animals.     (See  further  in  Calif.  Exp.  Sta.  Bull.  No.  150). 

The  following  list  includes  those  plants,  either  native  or  widely 
introduced,  which  are  either  definitely  known  to  be  poisonous  to  stock 
or  are  under  suspicion  but  which  seldom  if  ever  cause  serious  trouble 
in  California.  Plants  which  cause  injury  only  through  their  mechan- 
ical action  are  not  here  included.  All  species  in  which  the  amount 
of  toxicity  is  too  slight  to  be  of  interest  are  likewise  excluded. 

Pteris  aquilina  Common  Brake 

Equisetum  species Scouring  Bush,  Horse-tail 

Taxus    brevifolia    Western    Yew 

Typha    latifolia    Cat-tail 

Stipa    vaseyi    Sleepy-grass 

Lolium   temulentum   Darnel 

Agrostemma    githago    Corn  Cockle 


246  UNIVERSITY   OF    CALIFORNIA EXPERIMENT    STATION 

Aconitum  columbianum  Monkshood 

Actaea  rubra  Baneberry 

Anemone  quinquefolia  Wood  Anemone 

Calycanthus  occidentalis Sweet-scented  Shrub 

Ricinus    communis    Castor  Oil  Plant 

Euphorbia   species    Spurges 

Hypericum  concinnum Gold-wire 

Sanicula  bipinnata  Poison  Sanicle 

'Rhododendron    occidentale    Western  Azalea 

Rhododendron  californicum   California  Eose  Bay 

Apocynum    androsaemifolium    Small  Dogbane 

Apocynum  cannabinum  Indian  Hemp 

Nerium  oleander  Oleander 

Nicotiana  glauca  Tree  Tobacco 

Digitalis  purpurea  Foxglove 

Xanthium  species  Clotbur,  Cocklebur 

Helenium  puberulum Sneezeweed 

Helenium   hoopesii   Sneezeweed 


LIST  OF  ILLUSTRATIONS 

PAGE 

Water  Hemlock  (Cicuta  occidentalis)  223 

Death  Camas  (Zygadenus  venenosus)   227 

Tall  Mountain  Larkspur  {Delphinium  glaucum)  231 

Narrow-leaf  Milkweed  (Asclepias  mexicana)   233 

Lupine  (Lupinus  leucophyllus)   237 

Loco-weed  (Astragalus  hornii)   , 239 


ACKNOWLEDGMENT 

Grateful  acknowledgment  is  hereby  made  for  assistance  received  from  the 
United  States  Department  of  Agriculture.  During  the  preparation  of  this 
bulletin  the  authors  have  drawn  freely  upon  the  publications  of  that  institution 
and  more  especially  upon  those  of  Dr.  C.  Dwight  Marsh,  Dr.  Carl  L.  Alsberg, 
Mr.  V.  K.  Chesnut,  and  Mr.  A.  B.  Clawson.  They  have  also  had  the  pleasure  of 
consulting  personally  with  these  specialists  and  also  with  Dr.  R.  H.  True  of 
the  same  department,  and  here  desire  to  express  their  thanks  and  appreciation 
to  all  of  these  for  their  generous  assistance. 


Bulletin  249  STOCK  POISONING  PLANTS  OF  CALIFORNIA  247 


REFERENCES  TO  THE  LITERATURE 

The  following  titles  have  been  selected  from  a  long  list  as  being  of  practical 
value  to  veterinarians  and  stockmen  in  California. 

Chesnut,  V.   K.     Some   common  poisonous  plants.     Yearbook,   U.   S.   Dept. 

Agric.  1896,  pp.  137-146. 
Chesnut,  V.  K.     Thirty  poisonous  plants  of  the  United  States.     U.  S.  Dept. 

Agric.  Farmers'  Bull.   No.  86,  1898.      (Out  of  print) 
Chesnut,  V.  K.     Principal  poisonous  plants   of  the  United   States.     U.   S. 

Dept.  Agric.  Div.  Bot.  Bull.  No.  20,  1898.      (Out  of  print) 
Chesnut,  V.  K.  and  Wilcox,  E.  V.    The  stock-poisoning  plants  of  Montana. 

U.  S.  Dept.  Agric.  Div.  Bot.  Bull.  No.  26,  1901.     (Out  of  print) 
Chesnut,  V.  K.     Preliminary  catalogue  of  plants  poisonous  to  stock.     U.  S. 

Dept.   Agric.   Bur.   of   Animal  Industry   Rept.   for   1898,   pp.   387-420. 
Crawford,   Albert   C.     Mountain   laurel,   a   poisonous   plant.      U.    S.   Dept. 

Agric.  Bur.  of  Plant  Industry,  Bull.  No.  121,  pp.  21-35,  1908.      (Out 

of  print) 
Marsh,   C.  Dwight.     The  loco-weed  disease.     U.   S.  Dept.   Agric.  Farmers' 

Bull.  No.  380,  1909. 
Marsh,  C.  Dwight.    The  loco-weed  disease  of  the  plains.    U.  S.  Dept.  Agric. 

Bur.  of  Animal  Industry  Bull.  No.  112,  1909.     (Out  of  print) 
Marsh,  C.  Dwight.     Stock  poisoning  due  to  the   scarcity   of  food.     U.   S. 

Dept.  Agric.  Farmers'  Bull.  No.  536,  1913. 
Marsh,  C.  Dwight,  Alsberg,  C.  L.,  and  Black,  O.  F.    The  relation  of  barium 

to  the  loco-weed  disease.     U.  S.  Dept.  Agric.  Bur.  of  Plant  Industry, 

Bull.   No.   246,   1912.      (Technical   Bulletin    of   value   chiefly   to   spec- 
ialists) 
Marsh,  C.  Dwight,  Clawson,  A.  B.,  and  Marsh,  Hadleigh.     Larkspur,  or 

"Poison  Weed."     U.  S.  Dept.  Agric.  Farmers'  Bull.  No.  531,  1913. 
Marsh,   C.   Dwight,   Clawson,   A.   B.,   and  Marsh,   Hadleigh.      Cicuta,    or 

Water  Hemlock.     U.   S.  Dept.  Agric.  Bull.  No.   69,  1914. 
Pammel,    L.    H.      A    manual    of    poisonous    plants    (with    bibliography    by 

Harriette  S.  Kellogg).     Cedar  Rapids,  la.,  The  Torch  Press,  1911. 
Peters,  A.  T.,  Slade,  H.  B.,  and  Avery,  Samuel.     Poisoning  of  cattle  by 

common  sorghum  and  kafir  corn.     Nebraska  Exp.  Sta.,  Bull.  No.  77, 

1903. 
Slade,  H.  B.    Some  conditions  of  stock  poisoning  in  Idaho.    Idaho  Exp.  Sta., 

Bull.  No.  37,  1903,  pp.  159-190. 


STATION    PUBLICATIONS    AVAILABLE    FOR    DISTRIBUTION 


1897. 

1902. 
1903. 
1904. 
1914. 


No. 
116. 
168. 

169. 

170. 
174. 
177. 

178. 
182. 

183. 
184. 

185. 

186. 
195. 
197. 


198. 
203. 


207. 


REPORTS 

Resistant  Vines,  their  Selection,  Adaptation,  and  Grafting.     Appendix  to  Viticultural 

Report  for  1896. 
Report  of  the  Agricultural  Experiment  Station  for  1898-1901. 
Report  of  the  Agricultural  Experiment  Station  for   1901-03. 
Twenty-second  Report  of  the  Agricultural  Experiment  Station  for  1903-04. 
Report  of  the  College  of  Agriculture   and  the  Agricultural   Experiment   Station,   July, 

1913-June,   1914. 


BULLETINS 


The  California  Vine  Hopper. 

Observations  on  Some  Vine  Diseases 
in  Sonoma  County. 

Tolerance  of  the  Sugar  Beet  for 
Alkali. 

Studies  in  Grasshopper  Control. 

A  New  Wine-Cooling  Machine. 

A  New  Method  of  Making  Dry  Red 
Wine. 

Mosquito  Control. 

Analysis  of  Paris  Green  and  Lead 
Arsenate.  Proposed  Insecticide  Law. 

The   California   Tussock-moth. 

Report  of  the  Plant  Pathologist  to 
July  1,   1906. 

Report  of  Progress  in  Cereal  Investi- 
gations. 

Odium  of  the  Vine. 

The  California  Grape  Root-worm. 

Grape  Culture  in  California ;  Im- 
proved Methods  of  Wine-making ; 
Yeast  from  California  Grapes. 

The  Grape  Leaf-Hopper. 

Report  of  the  Plant  Pathologist  to 
July  1,   1909. 

The  Control  of  the  Argentine  Ant. 


No. 

208. 
211. 


212. 
213. 
215. 

216. 


224. 
225. 
227. 
230. 
234. 

240. 
241. 
242. 
243. 

244. 

245. 
246. 
247. 


The  Late  Blight  of  Celery. 

How  to  Increase  the  Yield  of  Wheat 

in  California. 
California  White  Wheats. 
The  Principles  of  Wine-making. 
The    House    Fly    in    its    Relation    to 

Public  Health. 
A    Progress    Report    upon    Soil    and 

Climatic     Factors     Influencing    the 

Composition  of  Wheat. 
The  Production  of  the  Lima  Bean. 
Tolerance  of  Eucalyptus  for  Alkali. 
Grape  Vinegar. 
Enological    Investigations. 
Red    Spiders    and    Mites    of    Citrus 

Trees. 
Commercial  Fertilizers. 
Vine  Pruning  in  California.     Part  I 
Humus  in  California   Soils. 
The     Intradermal     Test     for    Tuber 

culosis  in  Cattle  and  Hogs. 
Utilization  of  Waste  Oranges. 
Commercial  Fertilizers. 
Vine  Pruning  in  California,  Part  II. 
Irrigation  and  Measuring  Devices. 


No. 
46. 

62. 

65. 
68. 
69. 
70. 

75. 
76. 
79. 
80. 
82. 

83. 
84. 
87. 
88. 


98. 


100. 
101. 


102. 


CIRCULARS 

No. 


Suggestions  for  Garden  Work  in  Cali- 
fornia Schools. 

The  School  Garden  in  the  Course  of 
Study. 

The  California  Insecticide  Law. 

The  Prevention  of  Hog  Cholera. 

The  Extermination  of  Morning-Glory. 

Observation  of  the  Status  of  Corn 
Growing  in   California. 

A  New  Leakage  Gauge. 

Hot  Room  Callusing. 

List  of  Insecticide  Dealers. 

Boys'  and  Girls'  Clubs. 

The  Common  Ground  Squirrels  of 
California. 

Potato  Growing  Clubs. 

Mushrooms  and  Toadstools. 

Alfalfa. 

Advantages  to  the  Breeder  in  Test- 
ing his  Pure-bred  Cows  for  the 
Register  of  Merit. 

Disinfection  on  the  Farm. 

Infectious  Abortion  and  Sterility  in 
Cows. 

Plowing  and  Cultivating  Soils  in 
California. 

Pruning  Frosted  Citrus  Trees. 

Codling  Moth  Control  in  the  Sacra- 
mento Valley. 

The  Woolly  Aphis. 


106. 


107. 


108. 
109. 


110. 
111. 

112. 
113. 

114. 
115. 
116. 
117. 

118. 
119. 
120. 


121. 


122. 


123. 


Directions  for  using  Anti-Hog-Cholera 
Serum. 

Spraying  Walnut  Trees  for  Blight 
and  Aphis  Control. 

Grape  Juice. 

Community  or  Local  Extension  Work 
by  the  High  School  Agricultural 
Department. 

Green  Manuring  in   California. 

The  Use  of  Lime  and  Gypsum  on 
California   Soils. 

The  County  Farm  Adviser. 

Announcement    of    Correspondence 
Courses  in  Agriculture. 

Increasing  the  Duty  of  Water. 

Grafting  Vinifera  Vineyards. 

Silk  Worm  Experiments. 

The  Selection  and  Cost  of  a  Small 
Pumping  Plant. 

The  County  Farm  Bureau. 

Winery  Directions. 

Potato  Growing  in  the  San  Joaquin 
and  Sacramento  Deltas  of  Cali- 
fornia. 

Some  Things  the  Prospective  Settler 
Should  Know. 

The  Management  of  Strawberry  Soils 
in  Pajaro  Valley. 

Fundamental  Principles  of  Co-opera- 
tion in  Agriculture. 


